FIGURE 11.

Fluorescent, light, and electron microscopic observations of the cultured NHPH (A) By fluorescent immunohistochemical observation of the cultured NHPH using the HsvA antibody, many bacteria were observed in the incubation medium, X 400. Inset X 1800. (B) By light microscopic observation of the toluidine-blue stained Epon-embedded 2-µM section, many spiral bacilli were observed, X 600. Inset X 1800. (C) Electron microscopic observation of the cultured intact NHPH in pH 3. Intact bacilli were observed with flagella, X 15, 000. Ruthenium red en bloc staining. (D) Electron microscopic observation of the cultured NHPH in pH 6.5. Ruthenium red en bloc staining. The cytoplasm of some of the bacilli became condensed and homogeneous, and its plasma membrane became irregular, coinciding with the observation reported in the coccoid form, X 12,000, Inset x15, 000.